Photocatalytic properties of the CeO2‐xTiO2 and TiO2‐xCeO2 (x = 10, 30, and 50 mol%) heterostructures obtained by a MAH

• Published in: International journal of applied ceramic technology Vol. 17; no. 5; pp. 2376 - 2385
• Main Authors: Nascimento, Leulomar E., Andrade Neto, Nivaldo F., Ramalho, Onecima B. M., Bomio, Mauricio R. D., Motta, Fabiana V.
• Format: Journal Article
• Language: English
• Published: Malden Wiley Subscription Services, Inc 01.09.2020
• Subjects: Anatase; Catalytic activity; Cerium oxides; Heterostructures; Methylene blue; microwave‐assisted hydrothermal method; Nanospheres; Photocatalysis; photocatalytic reuse; Surface area; TiO2‐CeO2 heterostructures; Titanium dioxide; Transmission electron microscopy
• ISSN: 1546-542X; 1744-7402
• DOI: 10.1111/ijac.13575

In this work, CeO2‐TiO2 heterostructures were submitted to the microwave‐assisted hydrothermal (MAH) method at 140°C for 30 minute, and varying the CeO2 and TiO2 percentages as 10, 30, and 50 mol%. The heterostructures were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer‐Emmett‐Teller methodology (BET), and UV‐Vis diffuse reflectance spectroscopy (UV‐Vis). The photocatalytic properties were estimated varying the concentration of methylene blue (MB) dye. The diffractograms indicate the formation of TiO2 anatase and CeO2 phases, without the formation of secondary phases. TEM images indicate the formation of nanocubes and nanospheres for CeO2 and TiO2, respectively. BET analysis indicates that CeO2 has the largest surface area (62.80 m2.g−1), and TiO2‐10%CeO2 heterostructure has a low surface area (26.13 m2.g−1). The addition of TiO2 to CeO2 increases the photocatalytic activity from 32% to 80% for CeO2 and CeO2‐50%TiO2, respectively. In contrast, the addition of CeO2 significantly decreases the photocatalytic activity of TiO2 from 98.9% to 50% for TiO2 and TiO2‐50%CeO2, respectively. Reuse tests showed that the TiO2‐xCeO2 samples maintain the photocatalytic response in subsequent cycles while the CeO2‐xTiO2 samples have an increase in the response.